Of all the Rangers, I hold out hope that Saeradan and Lothrandir in particular survive.
In U11 we'll see Saeradan tell Halbarad that he wants to go back North to bury his fallen brothers in their own land. Halbarad gives him leave. So we may not see him for a while; he might miss the battles of the Hornburg and the Pelennor altogether.
I've already spoken my thoughts on Lothrandir: maybe we'll get to rescue him, but more likely he'll turn up somewhere and tells us (perhaps in a session play) how he escaped and served Lheu Brenin with his just deserts. Lothrandir is a Chekhov's gun; Turbine is going to do *something* interesting with him before all's done.